Here the relation \(\mu \preccurlyeq \nu ^{\prime }\)  is given in (REF ).
It is known that the unipotent characters are preserved by the \(\Theta _{,^{\prime }}\) 
(. [1]} theorem 3.5).
The following proposition on the \(\Theta \) -correspondence of unipotent characters
for a unitary dual pair
is rephrased from [2]} théorème 5.15 (see also [3]} proposition 5.13):
